I did reconnect with someone I lost track of a long time ago via google-stalking, found their email address. I'm pretty sure they agree that it was nice to reconnect, we talk regularly again.
(Neither of us are FB users, so no, it doesn't substitute.)
For this to be a downside, you have to believe that the person expressly wants to remove their email address from your view, but nevertheless wants to reconnect with you. That's possible, but I don't think a sane thing to build around.
I did reconnect with someone I lost track of a long time ago via google-stalking, found their email address. I'm pretty sure they agree that it was nice to reconnect, we talk regularly again.
(Neither of us are FB users, so no, it doesn't substitute.)